Komatsu PC60-7 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy For Excavator parts 201-26-71130 201-26-71180 201-26-71171 201-26-71170

Komatsu PC60‑7 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy For Excavator parts 201‑26‑71130 201‑26‑71180 201‑26‑71171 201‑26‑71170

Product Overview

This complete second‑stage planetary carrier spider and sun gear assembly functions as the secondary reduction transmission component installed within swing reducer of Komatsu PC60‑7 small‑size crawler excavator. It receives reduced torque output from the first‑stage planetary group, performs secondary speed reduction and torque multiplication, and transmits driving torque to actuate upper frame rotation. This compact machine is widely deployed for urban narrow‑space construction, residential foundation excavation, pipeline trenching, landscaping earth‑moving and small‑site renovation jobs. Subjected to frequent forward‑reverse slewing shock loads, ageing oil seals and degraded swing gear oil allow fine metal particles and construction dust to invade gearbox inner cavity, resulting in spline wear, gear tooth pitting, carrier spider deformation and pin‑hole oval distortion. Typical failure symptoms include persistent metallic grinding noise inside swing gearbox, discontinuous jerky cabin rotation, insufficient swing torque output, abnormal overheating on reducer housing, and metallic sediment detected during swing gear oil replacement. Manufactured strictly following original forging drawings and gear meshing parameters, this premium aftermarket assembly supports direct drop‑in replacement and avoids cascading damage to other expensive internal gearbox components.

Technical Specification

Core Advantages

1. Forged alloy build adapted for compact excavator secondary‑stage heavy impact transmission Carrier spider and matching sun gear are hot‑forged from high‑quality alloy steel blanks. After carburizing quenching heat treatment, gear tooth faces and internal splines obtain high surface hardness while maintaining adequate core toughness. The assembly can sustain cyclic impact torque generated by frequent digging‑swing combined actions, effectively lower risks of tooth chipping, spline scratching and carrier distortion under muddy and dusty job‑site operating conditions.
2. Pre‑verified gear meshing tolerance ensures stable and smooth slewing performance Each finished assembly undergoes tooth profile inspection and backlash measurement before shipment. Tightly controlled gear meshing clearance cuts down transmission vibration and friction‑caused grinding noise. When the mini excavator carries out combined boom‑arm‑bucket and swing compound movements, it delivers consistent power transfer and prevents cabin stutter or jerky rotation brought by poor gear fitting accuracy.
3. OEM‑replicated mounting structure shortens overhaul downtime for small‑machine maintenance Critical dimensions including carrier outer profile, sun‑gear spline specification, pin‑shaft hole layout and depth fully match OEM original standards. Field maintenance technicians can complete component swap directly without modifying gearbox housing or manually adjusting internal fitting gaps. For equipment rental firms and local repair workshops, it reduces machine stand‑still hours and economic loss caused by project interruption due to swing system failure.
4. Stress‑relief annealing eliminates residual stress generated from hot forging Stress‑relief annealing removes internal residual stress produced in hot forging process, enhancing long‑term structural stability under repeated cyclic shock loads. Combined with high‑precision machining for pin shaft holes and bearing mounting seats, it slows premature wear of mating planetary gears and bearings, extending total service life of the whole swing reduction assembly.
5. Economical partial‑repair alternative for small excavator fleets and repair workshops Rather than purchasing a complete high‑cost swing reducer unit, replacing only the worn second‑stage planetary carrier and sun‑gear assembly helps customers control maintenance expenditure. It is well‑suited for machinery repair shops, small construction contractors and global suppliers specialized in Komatsu small‑excavator spare‑parts wholesale business.

Manufacturing & Quality Control

Our production workshop specializes in planetary transmission spare parts for 5‑8 ton Komatsu small‑size excavator swing gearboxes. Full‑process quality supervision covers raw‑material composition verification, forging appearance inspection, heat‑treatment hardness testing, gear‑tooth precision detection, spline dimension validation and sample no‑load running‑in test. Only fully inspected‑qualified products enter packaging workflow. Finished assemblies are coated with anti‑rust preservation oil, wrapped with shock‑absorbing cushion materials and packed in export‑compliant fumigated wooden cases to prevent collision deformation and rust corrosion during long‑distance sea‑land multi‑modal logistics. We support bulk wholesale, stable batch supply, small trial orders are acceptable for worldwide purchasers.

Frequently Asked Questions

Q1: What abnormal phenomena indicate inspection or replacement of 2nd planetary carrier and sun‑gear assembly? A: If your Komatsu PC60‑7 excavator produces loud metallic grinding noise inside swing gearbox, cabin rotates jerkily and intermittently, swing power drops obviously, reducer housing suffers overheating, or metal particles are spotted in swing gear oil during oil‑drain maintenance, you should disassemble swing reducer for internal inspection in time.

Q2: Will this assembly fit other excavator models? A: This component is engineered for Komatsu PC60‑7 swing gearbox. Even though PC70‑7 shares partial similarities in appearance, internal gearbox configurations may vary. Please double‑verify OEM part numbers 201‑26‑71130, 201‑26‑71180, 201‑26‑71171, 201‑26‑71170 before placing your order to avoid installation mismatch.

Q3: What essential installation notes during gearbox overhaul? A: Completely remove all metal debris and old gear‑oil residue inside swing gearbox housing before installation. Meanwhile inspect wear condition of planetary gears, bearings and oil seals. After assembly completion, refill qualified swing gear oil, run low‑speed no‑load swing running‑in test before putting the excavator into formal construction work.

Q4: Warranty scope explanation A: Our warranty covers defects caused by raw‑material and manufacturing flaws. Damage resulting from foreign‑object intrusion, insufficient gear‑oil lubrication, severe overload impact and improper disassembly‑installation will not fall under warranty coverage. Please strictly comply with Komatsu official service manual for swing gearbox overhaul procedures.